The Russian Air Force will take another giant leap toward modernization at the end of this year when it receives the first batch of fifth-generation stealth fighter jets. The Sukhoi T-50, which is a joint program between India and Russia, will boost Russian air capabilities and make it the second country to have a functional fifth-generation jet fighter after the United States, which has the F-22 Raptor and is in final testing of the F-35 Lightning II.

But as the delivery date approaches, Russia’s relationship with India has suffered due to repeated delays and technical shortfalls, as well as Russia's unwillingness, claim Indian officials, to share vital details concerning the aircraft’s development.

“With India already having paid $295 million for the preliminary design and development costs, Russian unwillingness to share design information on the aircraft is not being received well in New Delhi," Monika Chansoria, senior fellow at the Centre for Land Warfare Studies think tank in New Delhi, told Defense News.

According to Chansoria, there has been a great deal of disenchantment in Indian military circles with the repeated delays and lack of cooperation from Russia, which may see India have to wait upwards of 10 years to have its own working version of the T-50.

When the deal for the jets was struck in 2007, it was aimed at heralding a new era for a vastly outdated Russian military, funded by a then-booming Russian economy. But now the aircraft’s introduction into the air force will come at a trying time for Russia financially and will be framed by the ongoing war in East Ukraine, which has been raging since April. While the blame for Russia’s ailing financial situation is primarily attached to falling global oil prices, sanctions placed against the country have prevented it from receiving international assistance and brought it close to recession.

The T-50 delivery also comes at the same time that the U.S.’ F-35 Lightning II is handed over to the U.S. Marine Corps to begin its operational life.